December 5: ORD

Today is December 5th. It's the 340th day of the year. 26 days remain. It's week 49 of the year.

Unless noted, the following data is based upon observations collected by the National Weather Service, Chicago, at O'Hare International Airport (ORD) between November 1978 and last year. Observations have been official at O'Hare since Thursday, January 17, 1980.

According to the National Climatic Data Center (NCDC), the normal high is 38 and the normal low is 24. The 30-year averages are 40 and 25.

On the warm side, in 1998 the high was 62 with the record warmest low of 55, a seven degree spread. Three years later, in 2001, the high was the record high of 68 with a low of 44. In 1982 the high was 63 with a low of 38. Three years earlier, in 1979, the high was 54 with a low of 37. One year later, in 1980, the high was 55 with a low of 36. In 1994 the high was 49 with a low of 37. Other warm lows were 33 in both 1989 and 1993. Once again, as I wrote yesterday, having a low above freezing (even if only a degree) is special this time of the year! 19 of the last 30 highs were 30s (10) and 40s (9). Five highs were 20s, two highs were 50s and three highs were 60s. One high was in the 10s.

In looking back through the years to the first December at O'Hare in 1958, the following instances were notable. In 1975 the high was 64 with a low of 46, a bonus 60s day. In 1972 the high was 30 with a low of 24, a six degree spread. In 1971 the high was 40 with a low of 36, a four degree spread. In 1966 the high was 39 with a low of 34, a five degree spread. In 1960 the high was 61 with a low of 41, a bonus 60s day.

More recently, the spread was three degrees in 1996 (34/31), five degrees in 1978 (36/31), five degrees in 1983 (37/32) and six degrees in 1997 (29/23).

On the cold side, in 2005 the high was the near-record coldest high of 17 with the record low of 4. The record coldest high of 15 was set way back in 1895. A year ago the high was 30 with a low of 9. In 2002 the high was 24 with a low of 15. A decade earlier, in 1992, the high was 25 with a low of 14. A year earlier, in 1991, the high was 33 with the near-record low of 6. In 1984 the high was 28 with a low of 11. Two years ago the high was 34 with a low of 7. In 2000 the high was 29 with a low of 12. This year will be one of the coldest as the low is already in the 0s and the high is predicted to be in the low 20s. 11 of the last 30 lows were in the 30s. Seven lows were 10s, six lows were 20s, four lows were 0s, one low was in the 40s and one low was in the 50s.

The following astronomical data is provided by the United States Naval Observatory. In Crystal Lake, twilight begins at 6:35 and sunrise is at 7:07. Chicago's twilight is three minutes earlier and sunrise is four minutes earlier. Sunset is at 16:21 and twilight ends at 16:53. Chicago's sunset is a minute earlier and end of twilight time is two minutes earlier. There's a total of 9 hours, 14 minutes of daylight today and 10 hours, 18 minutes between twilights. Tomorrow twilight begins at 6:36 and sunrise is at 7:08. The moon reaches first quarter today at 15:26. Illumination was 44% at midnight, will be 49% at noon and 54% at midnight tonight. Moonrise is at 12:01 and moonset is at 23:59, a minute before midnight. Moonlight time is 11 hours, 58 minutes.

Pearl Harbor Day is in two days. A sister of mine, Regina, will celebrate a birthday in nine days and Bill of Rights day is in ten days. Christmas Eve is in 19 days and Christmas Day is in 20 days. -Bernie-